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How do you
reduce annoying windshield glare especially at night? What does nitrous oxide do for a car? In racing, nitrous oxide or N2O is injected into the air intake to increase power. How does it do that? First of all, when N2O reaches a certain temperature, it breaks down and releases extra oxygen. Secondly, when the liquid in the tank vaporizes, it comes out extremely cold. The combination of these two effects allows you to cram a lot more oxygen into your cylinders. This extra oxygen creates additional power by allowing more fuel to be burned. The nitrogen component also acts to buffer, or dampen the increased cylinder pressures helping to control the combustion process. Now, exactly how much increased power are we talking about? For many applications an improvement from 1 to 3 full seconds in the quarter mile can be expected. The cooling effect alone can produce enough extra power so that a 350 HP engine can gain as much as 25 extra horsepower. Of course, a lot of factors such as tires, gearing, etc. will affect the final results. Of course, you only use nitrous oxide when you need it. Although it is possible to hold the button down until the bottle is empty, 15 continuous seconds at a time, or less, is recommended. One last thing, N20 is also sometimes incorrectly referred to as NOS. Those three letters are actually an acronym for Nitrous Oxide Systems, the world’s largest marketer of nitrous oxide injection systems for automotive use. What is the overdrive function in an automatic transmission?Overdrive is really just a fancier name for the highest gear on your vehicle. When you switch it on, you allow your transmission to shift into Overdrive mode after your vehicle hits a certain speed. In effect, it reduces the revolutions per minute (rpm) thereby improving fuel efficiency while you’re driving on the highway. When it’s off, you limit shifting to the second highest gear.Obviously, with an automatic transmission, the gears are shifted automatically by the vehicle. But then again, overdrive can be turned on or off. So the question has cropped up as to whether it is necessary to manually shift to overdrive. The answer is no. As a general rule, you should just turn the overdrive on and forget about it. Under normal driving conditions, your vehicle will automatically shift into overdrive, slow the engine and save gas as soon as you hit a certain speed.However, there are times when you might want to take the transmission out of overdrive. That’s when certain road or traffic conditions force you to maintain a speed that keeps the transmission on the blurry edge between the second highest gear and overdrive, and so you find the transmission “hunting”. That’s when the transmission keeps shifting back and forth a lot, “hunting” for the right gear to be in. This usually happens when you’re driving uphill or towing something and your vehicle can’t decide whether to stay on overdrive or shift to a lower gear.It doesn’t hurt the transmission if it keeps doing that. But it can get rather annoying to the driver. So you can temporarily take the transmission out of overdrive until the road or driving conditions change. Now, if you forget to turn overdrive back on and drive for quite some distance again at high speed, you'd put a little extra wear on the engine and get poorer gas mileage. So if you turn it off, remember to turn it back on.What is an oxygen sensor? The oxygen sensor is part of your car’s emissions control system, which is a system that monitors how your engine is running by analyzing the exhaust. Several times a second, the oxygen sensor feeds information to your car’s computer so it can determine if the right amount of air and fuel is going into the cylinders. If the oxygen sensor detects too much oxygen in the exhaust, that indicates the mixture is running too lean – meaning there’s too much air and not enough fuel. A lean-running engine can produce more nitrogen-oxide pollutants, and in some cases, can cause poor performance and even engine damage, so the computer adds more fuel to compensate. If the sensor detects too little oxygen in the exhaust, that means the mixture is too rich -- that means there’s too much fuel and not enough air. Rich mixtures are also bad because the unburned fuel creates pollution with increased hydrocarbon emissions, so the computer makes the necessary adjustments. These air/fuel mixture adjustments take place continuously -- many times a minute to make sure the ratio is always perfect. This improves fuel economy, cuts down on pollution, and extends the life of the catalytic converter. If you have a failed oxygen sensor, you may be tipped off by the following symptoms:
Older cars with no computers simply have a warning light on the dashboard which the oxygen sensor switches on to tell you it’s time to take your car to Kuya Mike for a checkup! What is the difference between an OEM piston and a forged piston? Most OEM or original equipment pistons are manufactured through casting. That is, by pouring a liquid or molten aluminum-silicon alloy into a mold. Forged pistons use a solid ingot or billet that is stamped into shape. What difference does that make? For one thing, although standard cast pistons can be very strong and light, in high performance situations, a cast piston is more likely to shatter and damage the rest of the engine. Forged pistons tend to be stronger at high temperatures because they dissipate heat better and run cooler than cast pistons. However, because of manufacturing procedures, forged pistons are much more expensive. The big advantage that makes them worth their price is that in extremely high rpm or high horsepower applications, the strength of the forged piston is far more reliable. In case of abnormal combustion, forged pistons have a more supple or ductile material that can take a higher level of detonation before failing. But then again, if you’re just building a mildly souped-up engine that’s tuned well enough not to detonate in the first place, then there’s really no point in blowing all that money on a forged piston. Of course, different engine designers have their own opinions as to what power level it becomes necessary to change from a conventional cast piston to a forged one. But it would be safe to say that once power levels rise past about 80 horsepower per liter of engine capacity, then a forged piston becomes worth it. Is it okay to port and polish the engine of a daily driven car? Perhaps the question should be, “Is it practical?” First, let’s explain what it means to ‘port and polish’. As you may know, the casting process involved in the production of cylinder heads leaves behind some rough areas inside the intake and exhaust ports. Considering the large quantities involved in the mass production of cars, manufacturers can only pay little, if any, attention to dressing the ports of the cylinder head after it has been cast. Basic cylinder head porting removes any casting imperfections and just by smoothing out the surfaces, you reduce restriction and let more air into the cylinders. With more air, you can add more fuel and that leads to increased horsepower. Exactly how much extra power can you get out of your cylinder head through porting and polishing? If you’re just talking about a 100 BHP engine, it won’t amount to much, perhaps no more than an extra 5 BHP. But for a 300 HP engine, you can probably add as much as 10 -15 BHP. The bigger the increase in the rate of air flow and exhaust gases, the more the potential of porting and polishing is realized. Now, if we tackle the practicality of porting and polishing a daily driven car, keep in mind that this also leads to an increase in fuel consumption. And if most of the driving you do in the city means you travel one kilometer an hour through rush hour traffic, there wouldn’t be much sense to it. Basic head porting is usually done for street high-performance, drag-racing or weekend racer applications.
I've been driving
automatic transmission cars. Given our traffic condition here, is it
better to shift to Neutral or just keep it on Drive while pressing on the
brake pedal? But the truth is, every time you shift from Neutral and back to Drive, you cause more wear on the moving parts because you repeatedly relax and engage the components of the drive train. But don’t worry about it too much if you’ve been doing that. It really doesn’t do much harm to your car; it just means some parts will wear out a little sooner than they should. If you’re talking about short stops, say for a red light, you can leave the car in gear, but keep one foot on the brake to prevent “creeping”. (It’s not because the car might “run away” accidentally.) To save on gas and to keep from overheating the transmission, never accelerate while the brake is engaged, while holding the vehicle on an incline or while waiting for the light to change. Just use your brake. In heavy stop-and-go traffic, especially in hot weather, some owner’s manuals recommend using the number 2 position. But, since we do get some monster traffic jams around here, there will be occasions when shifting to Neutral is recommended. If you know you’re going to be sitting still for quite some time with the engine running, always place the lever in neutral or park with the parking brake engaged. If it’s a prolonged stop and you stay on “Drive” with your foot on the brake, some added strain is put on your vehicle’s cooling system. By shifting to Neutral with your foot on the brake, the gear is released and the transmission develops less heat. By keeping the temperature down, you protect the fluid and the internal parts of the transmission. But remember, shifting to Neutral is only recommended if you’ll be sitting with the engine running for an extended period of time. How do I know when to replace my shock absorbers? Shock absorbers wear out slowly, which is why changes in handling often pass unnoticed until there is a sudden failure. That means even as you are using your car in the normal manner, road holding, braking and comfort are gradually deteriorating without you realizing it. The most familiar test used for shock absorbers is what you could call the “bounce test”. Push down with your whole body weight on each corner of the vehicle and quickly let the body back up. The vehicle should bounce up, back down, and then up one more time. This shows the valves inside the shock are working properly. If the car bounces more than three times when doing this test, the shocks definitely need replacement. Unfortunately, this test will only tell you the condition of the shocks when they are already very bad. If the car dips and then recovers immediately without any further bounce, the shocks may be fine, but could still be below par when it comes to small movements. Shocks can also be checked visually. The shock absorbers should be dry, and the shock's boots should not be damaged. Wet oil on the outside of the assembly means it needs replacing. When fluid starts leaking out of the shock, in a very short time (if not already) it will stop working, making your car unsafe to drive. A worn shock absorber allows the tires to bounce too much causing a reduced grip on the road and dangerous steering instability. This can result in loss of control. Worn shock absorbers can also result in abnormal wear of the tire tread and affect ride and handling, and in the long run wreak havoc on alignment and the entire suspension system. To be on the safe side, manufacturers recommend regular checks every 15,000 km by an experienced technician. How will I know if my spark plugs need to be replaced? Spark plugs create the spark that ignites the air and fuel mixture in your engine. If your vehicle has a hard time starting, is misfiring, is missing and running rough or has low power and poor fuel mileage -- it may be because not all of your spark plugs are firing properly. Worn spark plugs can be caused by simple lack of proper servicing and not changing them at the recommended intervals. Or they could be eroded by chemical additives in your fuel or be fouled by carbon, oil or extended high-speed operation. Melting, insulator breakage, glazing or blistering can also be caused by a number of things from certain driving conditions to overheating and detonation. Part of your regular engine tune-up should include the replacement of the spark plugs and spark-plug wires. Older vehicles are typically tuned every 40,000 kms. But newer ones can go as far as 100,000 to 160,000 kms before the first major tune-up. This is also thanks in part to today’s platinum tipped spark plugs. But even if your vehicle is a newer model, it’s still best to check the spark plugs every 40,000 kms. In all cases of fouling or wear, it is best to replace the plugs. It’s also advisable to replace the entire set, even though only one plug may be bad. And you should replace the spark-plug wires too. When do you need to change your timing belt? The timing belt is responsible for ensuring that the pistons, injector pump, inlet and exhaust valves are at the right place at the right time during the 4-stroke cycle. Otherwise, these parts could collide, with your pistons crushing your valves and they, as well as other parts of the engine, will be damaged. If you’re cruising down the highway and your timing belt breaks, you’d lose power, have no power steering, and your brakes will no longer be power assisted so it will take longer for you to stop. The extent of the engine damage is difficult to predict and it varies depending on certain conditions. The auto makers say that timing belts should be replaced at the time or mileage interval specified in your owner's manual, regardless of the physical appearance of the belt because a timing belt can have hidden damage. The replacement period is generally in a range between 80,000 and 160,000 km depending on the vehicle and how it is used. Independent technicians agree with the manufacturers, but to be safe, they also recommend that the belt be inspected between 48,000 and 80,000 km. The most practical time to check the belt is during a tune-up, while the spark plugs are out and there is no engine compression. A simple inspection may involve rotating the drive and feeling for slack or play in the belt. On some engines, the belt guard can be partially pulled away for a quick visual inspection. The most thorough inspection, however, involves removing the belt cover to check every tooth and land (the flat area between the teeth). But as mentioned above, the timing belt could have hidden damage so regardless of the appearance, it’s best to replace it within the interval specified in your owner’s manual and have it inspected every 48,000 and 80,000 km. What is 23 psi? How much air should I put? Psi is a unit of pressure that stands for pounds per square inch. So if your tire pressure gauge reads 23 psi, that means the air inside is exerting a pressure of 23 pounds per square inch against your tire wall. Most drivers can improve fuel mileage by at least two percent just by keeping their tires at the recommended pressures. And take note: A tire can lose up to half of its air pressure and not appear to be flat! Under-inflation results in unnecessary tire stress, irregular wear, loss of control and, worst of all, accidents. So how much air should you put in your tires? Most car manufacturers recommend pressures that are equal or close to the maximum pressure molded into the tire sidewall. But, it’s best that you check out the car maker's recommended tire pressures in your owner's manual, or look for a sticker or placard in the glove compartment or on the driver's door post. Keep in mind that these are cold inflation pressures. This means that the pressure should be checked and adjusted when the tire is completely cold or after driving less than one mile. So if you have to drive somewhere to check your tire pressure, don’t forget that the pressure in a tire rises as the vehicle is driven. So never let air out of a hot tire to reduce pressure to a cold-inflation recommendation. But what’s the criteria car manufacturers have in determining ideal tire pressure? Naturally there’s ride comfort. Then there’s load capacity, traction, rolling resistance, wear and of course, fuel economy. But sometimes front and rear tires can have different pressure recommendations. That’s because the manufacturer is aiming to balance front to rear handling, tracking and other characteristics by adjusting the tire pressures. So if you ignore your car manual’s recommendations and add the same air pressure in front as the rear, you will change the handling characteristics from what the manufacturer intended. So if you’ve got a vehicle with different pressures for the front and rear, don’t forget that detail whenever you rotate your tires or change a flat.
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